Solved: Finding Marketing Agencies for Fast-Growing Startups

Hi there,

Thanks for reaching out. It’s a common question and a bit of a minefield trying to find the right partner when you're growing fast. Happy to give you some of my initial thoughts and a bit of guidance based on my experience running paid ad campaigns for startups like yours. The real trick isn't just finding *an* agency, it's finding a partner that actually understands the mechanics of growth and won't just burn your cash on vanity metrics.

Let's get into it.

We'll need to look at who you're trusting with your budget...

First off, you're right to be sceptical of those review sites. A lot of them are pay-to-play. The single most reliable piece of evidence you have is their case studies. But even then, you need to know what you're looking for. It's not about finding an agency that's worked with a huge, recognisable brand. That's a classic vanity trap. What you need to find is an agency that has driven measurable results for a business that looks something like yours – similar stage, similar niche, similar business model.

Don't be impressed by a slide with the Nike or Google logo on it. Ask them: "What did you actually do for them? What was the ROAS? What was the cost per acquisition? By how much did you increase their qualified leads?" If they get cagey or talk in vague terms about 'brand awareness' and 'engagement', that's a big red flag. You're a fast-growing startup; you don't have the luxury of spending money on metrics that don't directly contribute to revenue or user growth.

I remember one campaign where we worked with a medical job matching SaaS client, and when we took over, their Cost Per User Acquisition was about £100. It was crippling them. We managed to get it down to £7. That's a specific, tangible result that changed the entire economic model of their business. Another B2B SaaS client we helped was struggling to get trials; we set up some campaigns on Meta and brought in over 1,500 trials. Or for another software business, we generated over 5,000 trials at a $7 cost per trial. These are the kinds of numbers you want to hear. That's the language of growth. Anything else is just noise.

So, when you're looking at their case studies, analyse them. Do they actually walk you through the problem, the strategy they implemented, and the results? Or is it just a glossy PDF with a client logo and a fluffy testimonial? The best agencies are proud of their work and will want to show you the engine, not just the shiny paint job. If you see a claim like "$115k Revenue generated in 1.5 Months for a course", ask them what the ad spend was. That figure is useless without the context of the return on investment.

And one last thing on this. If you get through the case studies, get on a call, and you still feel like you need to speak to one of their current clients for a reference, it's probably not the right fit. For us, that's often a sign that the trust isn't there from the start. A good agency's expertise and track record should speak for itself during the process. If it doesn't, you should probably walk away.

I'd say you need to define your customer's nightmare...

Here’s a contrarian thought for you: a great agency will spend more time in the first call asking you questions than they do talking about themselves. The most important question they can ask isn't about your budget. It’s "Who is your customer, and what is the expensive, urgent, career-threatening nightmare that your product solves for them?"

Forget the bland, demographic-based Ideal Customer Profile (ICP) you might have. "SMEs in the tech sector with 50-200 employees" is a useless starting point for advertising. It tells you nothing of value and it leads to generic, boring ads that try to speak to everyone and end up convincing no one. You have to stop thinking about your customer as a demographic and start thinking of them as being in a specific problem state.

Your ICP isn't a person; it's a pain point. It’s a moment of intense frustration. Let me give you an example. Say you sell a B2B SaaS tool for developers. Your ICP isn't "Head of Engineering at a Series B startup". It's a leader who is terrified that her best three developers are about to quit because they're so fed up with a clunky, broken internal workflow. She isn't looking for "workflow automation software"; she's looking for a way to stop the talent bleed that's threatening her entire product roadmap. See the difference? One is a job title, the other is a raw, emotional driver for a purchase.

For a legal tech SaaS, the nightmare isn't 'needing better document management'. It's a senior partner waking up in a cold sweat at 3 AM because he thinks he might have missed a critical filing deadline, exposing the entire firm to a multi-million-pound malpractice lawsuit. You don't sell document management; you sell peace of mind and career preservation.

Once you've isolated that very specific nightmare, your entire targeting strategy becomes clear. Where does this person go to find solutions? What niche podcasts do they listen to on their commute, like 'Acquired'? What industry newsletters do they actually read, like 'Stratechery'? What SaaS tools are they already paying for, like HubSpot or Salesforce? Are they members of the 'SaaS Growth Hacks' Facebook group? Do they follow people like Jason Lemkin on Twitter for advice?

This isn't just market research; it's the blueprint for your ad campaigns. This intelligence tells you exactly where to place your ads and what your ad copy needs to say. Any agency that doesn't push you to this level of clarity about your customer's pain before they even think about building a campaign is just going to take your money and pour it down the drain. You need to do this work first, or you have no business spending a single pound on ads.

You probably should understand the maths that unlocks real growth...

Once you know who you're targeting and what their nightmare is, the next question a good partner will obsess over is your unit economics. Most founders are fixated on the wrong question. They ask, "How low can I get my Cost Per Lead (CPL)?" The real question, the one that separates startups that scale from those that stagnate, is "How high a CPL can I afford to acquire a truly great customer?"

The answer lies in your Customer Lifetime Value (LTV). If an agency isn't talking to you about LTV and its relationship with Customer Acquisition Cost (CAC), they are fundamentally not a growth partner. They're just a media buyer. Here’s how you should be thinking about it.

You need to know three numbers:

• -> Average Revenue Per Account (ARPA): What's the average amount a customer pays you per month?
• -> Gross Margin %: What's your profit margin on that revenue after accounting for costs of service/goods?
• -> Monthly Churn Rate: What percentage of your customers do you lose each month?

The calculation is simple but powerful: LTV = (ARPA * Gross Margin %) / Monthly Churn Rate

Let's run through a quick, hypothetical example for a B2B SaaS startup. I've put it in a table to make it clearer.

So, in this scenario, every new customer you acquire is worth £6,800 in gross margin to your business over their lifetime. This number changes everything. It's your North Star for paid acquisition.

A healthy, sustainable business model for a venture-backed startup often aims for an LTV to CAC ratio of at least 3:1. This means for every £1 you spend to acquire a customer, you should expect to get at least £3 back in lifetime gross margin. With a £6,800 LTV, this means you can afford to spend up to £2,266 to acquire a single new customer.

Now, work backwards. If your sales team (or your automated funnel) converts 1 in 10 qualified leads into a paying customer, you can afford to pay up to £226 for that single qualified lead. Suddenly, that £150 lead from a LinkedIn campaign targeting senior decision-makers doesn't look so expensive anymore, does it? It looks like a bargain. This is the math that frees you from the tyranny of chasing cheap, low-quality leads and allows you to aggressively and intelligently outbid competitors for the customers that really matter.

You'll need an offer they can't refuse...

Now we get to the most common point of failure in almost all B2B and high-ticket advertising: the offer. You can have the best targeting in the world and the perfect ads, but if you send that traffic to an offer that asks for too much and gives too little, your campaign will fail. It's that simple.

I want you to go to your website right now and look at your main call to action. Does it say "Request a Demo"? If it does, you should seriously consider deleting it. The "Request a Demo" button is one of the most arrogant and ineffective calls to action ever invented. It presumes that your prospect, a busy and important person, has nothing better to do with their time than schedule a meeting to sit through a sales pitch. It is high-friction, low-value, and it instantly positions you as just another commodity vendor clamouring for their attention.

Your offer has one job and one job only: to deliver a moment of undeniable value. An "aha!" moment that is so powerful it makes the prospect sell themselves on your solution. You need to solve a small, real problem for them for free to earn the right to ask them to pay you to solve the whole thing.

If you're a SaaS founder, this is your ultimate advantage. The gold standard offer is a free trial (with no credit card required) or a freemium plan. Let them actually use the product. Let them experience the transformation firsthand. When the product itself proves its own value, the sale becomes a simple formality. You're no longer generating "Marketing Qualified Leads" (MQLs) for a sales team to chase down; you're creating "Product Qualified Leads" (PQLs) who are already convinced and are asking you how they can pay.

If you're not a SaaS company, you're not off the hook. You must find a way to bottle your expertise into a tool, an asset, or a piece of content that provides immediate value. For a marketing agency, this could be a free, automated SEO audit that instantly shows a prospect their top three missed keyword opportunities. For a data analytics platform, a free 'Data Health Check' that flags the biggest issues in their database. For a corporate training company, a free 15-minute interactive video module on 'How to Handle Difficult Conversations' for new managers. For us, as a B2B advertising consultancy, our irresistible offer is a free 20-minute strategy session where we get on a call and audit a startup's failing ad campaigns, showing them exactly what we'd do to fix it. This demonstrates expertise and builds trust far more effectively than any sales pitch ever could.

This is the main advice I have for you:

To pull this all together, here is a quick overview of how you should be thinking about finding and working with an agency to fuel your growth. It's about shifting your mindset from how things are commonly done to an approach that actually works for a fast-growing business.

Hopefully, this framework gives you a much clearer lens through which to evaluate potential partners. It's less about the agency's sales pitch and more about their fundamental approach to growth. An agency that embodies these principles is one that can become a true extension of your team, not just another vendor on your expense sheet.

The whole process is about de-risking your investment in paid ads. By focusing on these core pillars—provable results, deep customer understanding, sound economics, and an irresistible offer—you move from gambling to making calculated investments in your startup's future.

Finding the right agency is a huge decision, and the right partner can be the difference between stagnating and hitting your next growth milestone. It takes time to get this stuff right, and the learning curve can be expensive if you try to do it all yourself. Getting expert help can shortcut that process and help you avoid the common pitfalls that burn through startup capital with little to show for it.

If you'd like to chat through your specific situation and see how these principles could be applied to your startup, we offer a free, no-obligation initial strategy session where we can take a look at what you're doing and give you some actionable advice. It might be a good first step for you.

Regards,

Team @ Lukas Holschuh